The over all flow of a story is dependent upon the nature of the story itself. Normally, I just write it as I see fit, and let it go the way it naturally needs to come about. If you start inserting things simply to lengthen the piece, then it won't work out well in the end.
I'm not sure how long you intend your work to be, but the longest of mine is about 10, if that's any help.
What are you looking for, as far as advice is concerned? I can give some techniques for lengthening, but just using them to use them isn't really the best of advice, so could you please be more specific? Thanks.
Etc.
Editing to expand upon this with examples.
For example, one thing I had written involved a woman being knocked out with chloroform, or something or other (I didn't include a specific then due to it's first person nature(third, not omni specifically, so it only followed that persons viewpoint), though it was actually third if I recall - she wouldn't have known), waking up within the next paragraph, barefoot and alone in a chair. Another paragraph for the description of the room, and the tickling had ensued. Jumping into the tickling (well not exactly but close enough) worked for this story for a lot of reasons, the major of which being the viewpoint. Had it been from the kidnappers viewpoint, though, it would have been a much more arduous beginning. She would have to plan the kidnapping, hide in the lab, do the chloroform thing, then transport and prepare her victim for the tickling. It's much different.
I mean, if I need to pass two days or so, then it needs to feel like two days. It can't just be, oh she woke up and went to sleep, or traveled twenty odd hours to this place. That just doesn't work. The character needs to travel; needs to describe the boringness of traveling, and take notice of particular trees or clouds that don't necessarily stand out, but catch her interest simply because there is nothing going on. If, say, she were running from home, and was not to arrive at the destination where I want the tickling to ensue for another week... it would be silly of me to begin the tickling immediately. But then, I could also start it off as she is in the stockade or whatever, and is flashing back to the events that led up to it, but I certainly wouldn't be able to include the non-chalantness of life that way, as that tree or that cloud wouldn't have made a lasting impression on the character, anyway.
I think the point I'm trying to make is that it's a case-by-case call. There are any number of a hundred or so small things you can do, from description to inserting sub plots, but if the story doesn't call for them on it's own, then recommending them is silly.
Double etc. Or etc. squared.
